<template>
  <div class="todo-footer">
    <label>
      <input type="checkbox"
             v-model="allCheck" />
    </label>
    <span>
      <span>已完成{{doneCount}}</span> / 全部{{total}}
    </span>
    <button class="btn btn-danger"
            @click="deleteAllDone">清除已完成任务</button>
  </div>
</template>

<script>
  export default {
    name:'Footer',
    props:['deleteAllDone','todos','checkAllTodo'],
    computed: {
        doneCount(){
            return this.todos.reduce((pre,curr)=> pre + (curr.done ? 1 : 0),0)
        },
        total(){
            return this.todos.length
        },
        
        allCheck:{
            get(){
                return (this.doneCount === this.total)&&(this.total > 0)
            },
            //通知app全选or全不选
            set(val){
             this.checkAllTodo(val)
            }
       
        }

   
    },
  }
</script>

<style scoped>
/*footer*/
.todo-footer {
  height: 40px;
  line-height: 40px;
  padding-left: 6px;
  margin-top: 5px;
}

.todo-footer label {
  display: inline-block;
  margin-right: 20px;
  cursor: pointer;
}

.todo-footer label input {
  position: relative;
  top: -1px;
  vertical-align: middle;
  margin-right: 5px;
}

.todo-footer button {
  float: right;
  margin-top: 5px;
}
</style>